Download Trade of Motor Mechanic Module 2

Phase
2
Trade of Motor Mechanic
Module 2
Unit 6
Body Wiring,
Lighting Circuits
Produced by
In cooperation with:
Subject Matter Experts
Martin McMahon
&
CDX Global
Curriculum Revision 2.2 16-01-07
© SOLAS 2013
Module 2 - Unit 6
Body Wiring, Lighting Circuits
Table of Contents
Introduction......................................................................................................... 1
Unit Objective...................................................................................................... 1
1.0 Schematic Electrical Wiring Diagram...................................................... 3
1.1
Layout of Electrical Circuits......................................................... 3
1.2 Component Identification ‘Group’ Codes..................................... 5
1.3 Connecting Wire Colour Code....................................................... 5
1.4 Example Wiring Diagrams............................................................ 6
1.5 Symbols and Codes Used in the Example Diagrams................... 6
2.0 Primary Terminal Designation................................................................. 7
2.1 Electrical Connection (DIN) Numbers........................................ 7
3.0 Electrical Connectors and Their Function............................................... 9
3.1 Physical Requirements of Electrical Connections........................ 9
3.2 Operational Requirements of Electrical Connections.................. 9
3.3 Service Requirements of Electrical Connectors..........................10
3.4 Consequences of Faulty Electrical Connections.........................10
3.5 Gold and Tin Coated Terminal Ends...........................................10
4.0 Electromagnetic Relays and a Solenoids................................................ 11
4.1 Electromagnetic Relays................................................................ 11
4.2Solenoids.......................................................................................12
5.0 Relays in Lighting Circuits......................................................................13
6.0 Terminal Designations of a Trailer Wiring Socket/Plug........................13
6.1 Trailer Wiring Socket....................................................................13
7.0 The Basic Multiple Position Switch Symbol...........................................14
8.0 Basic Dual/Triple Branch Parallel Circuits............................................14
9.0 Basic Schematic Wiring Diagrams..........................................................15
9.1 Automotive Electrical Symbols.....................................................15
10.0 Switch Controlled Fused Lighting Circuits.............................................18
10.1 Sample Circuit Diagrams.............................................................18
11.0 Relay Controlled Auxiliary Lighting Circuits......................................... 28
12.0 To Connect a Trailer Light Assembly.................................................... 28
13.0 Diagram of Basic Standard Circuits...................................................... 28
14.0 The Term 'BUS' as Used in Automotive Electrical Systems................. 29
14.1’ BUS’ Explained............................................................................ 29
15.0 In-Vehicle Network Developments....................................................... 30
15.1 Networking & Multiplexing........................................................ 30
16.0 Location and Voltage Drops on the Earth Connections.........................31
17.0 Tungsten, Halogen and Xenon Bulbs.....................................................31
17.1 Light Bulbs...................................................................................31
17.2 Xenon HID Headlights............................................................... 33
18.0 Servicing Lamps..................................................................................... 34
19.0 NCT/DoT VTM Regulations for Condition of Lamps......................... 34
19.1 NCT Body Wiring and Lighting Circuit Requirements............. 34
20.0 Focusing Headlights.............................................................................. 35
21.0 Diagnosing Electrical Circuits............................................................... 35
22.0 The Effect of Wrong Fuse or Bulb......................................................... 36
22.1Fuses............................................................................................ 36
23.0 Crimped Joints on Light Cables............................................................. 37
23.1 Stripping Wire Insulation............................................................ 37
Self Assessment................................................................................................. 40
Suggested Exercises.......................................................................................... 42
Training Resources............................................................................................ 42
Trade of Motor Mechanic - Phase 2 Course Notes
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Module 2 - Unit 6
Body Wiring, Lighting Circuits
Task Sheets........................................................................................................ 43
Aiming Headlights................................................................................. 43
Checking & Changing a Headlight Bulb............................................... 44
Checking & Changing an Exterior Light Bulb...................................... 46
Checking Lighting & Peripheral Systems.............................................. 48
Suggested Further Reading............................................................................... 50
Trade of Motor Mechanic - Phase 2 Course Notes
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Module 2 - Unit 6
Body Wiring, Lighting Circuits
Introduction
There are six Units in this Module. In Theory 1 we cover Units 1,
2 and 3 which focuses on the basics of electricity. In Theory 2 we
cover Units 4, 5 and 6 which focuses on the fundamental electrical
circuits in the vehicle.
Module 2
Body
Electrics
Unit 4
Alternator/
Circuit
Unit 5
Starter Motor/
Circuit
Unit 6
Body Wiring
Lighting Circuits
In Unit six it describes the basic function and operation of the body
wiring, lighting circuits. You will receive instruction on how to read
and interpret basic schematic electrical wiring diagrams. Be able to
identify and state the primary terminal designation codes used by the
major automobile manufacturers. Describe the function and basic
requirements of automotive electrical connectors, electromagnetic
relay and a solenoid.
On completion of this unit you will be able to interpret/draw basic
schematic wiring diagrams of body wiring, lighting circuits and
ancillary components. You will be able to test and adjust/repair as
required to NCT/DoT VTM (Department of Transport Vehicle
Testers’ Manual) specification.
Unit Objective
•
Read and interpret basic schematic electrical wiring diagrams
•
State the primary terminal designation codes used by the major
automobile manufacturers in basic standard dual filament head
and parking light circuits
•
Describe the function and basic requirements of automotive
electrical connectors
•
Describe the function and operation of an electromagnetic relay
and a solenoid
•
State the function of relays in lighting circuits
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Body Wiring, Lighting Circuits
•
State the terminal designations of a general relay and a trailer
wiring socket/plug
•
Draw a basic multiple position switch symbol
•
Draw basic dual/triple branch parallel circuits that use a multiple
position switch to control differing combinations of branch
loads/circuits e.g. D.P.S.T., D.P.D.T.
•
Draw basic schematic wiring diagrams of; parking, brake,
reversing, head/dim lighting circuits, also of relay controlled
auxiliary light circuit
•
Construct basic switch controlled fused; parking, brake, reversing,
head/dim lighting circuits
•
Construct a relay controlled auxiliary lighting circuit
•
Connect a trailer light assembly
•
From manufacturer’s diagrams, draw the schematic wiring
diagram of identified basic standard circuits e.g. fuel pump,
heated screen, oil pressure, coolant/fluid level
•
Describe the reasons for the development of the integration (invehicle networks) of the electronic control units in automotive
use
•
Define the term 'BUS' as used in automotive electrical multiplex
network wiring systems
•
Report the location and voltage drops on the earth connections
for identified primary electrical circuits (e.g. lights, fuel pump)
•
Identify tungsten, halogen and xenon bulbs and describe their
correct fitting procedure
•
Remove/refit tungsten, halogen and xenon bulbs on training
units/vehicles
•
Describe the NCT/DoT VTM regulations for condition of
front, auxiliary, rear, warning and reflectors, aim of front and
auxiliary lamps
•
Focus headlights to NCT/DoT VTM standard
•
Measure quantities of current, voltage and electrical resistance,
also to diagnose electrical circuit faults e.g. open, shorts, voltage
drops/loss on basic lighting circuits of an operational vehicle
•
State the effect of the fitting of a wrong amperage fuse or
incorrect type of bulb.
•
Make up crimped joints on light cables
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Body Wiring, Lighting Circuits
1.0 Schematic Electrical Wiring
Diagram
Key Learning Points
•
Circuit diagrams that demonstrate switch controlled/switch
and relay series and parallel/series-parallel circuits with
bulbs, resistors and motors etc. as loads.
1.1 Layout of Electrical Circuits
The layout of electrical circuits and their components are shown as
diagrams made up of symbols and connecting lines. Being able to
read a circuit diagram is important when trying to trace and correct
a fault in an electrical system. However, all manufacturers do not
use the exact same symbols, codes or terminal numbers, but for you
to get a successful beginning at reading wiring diagrams, it is best
to follow one common system. The system described here is based
on the European DIN standard that generally has current flowing
from top (Terminal No.30) to the bottom earth (Terminal No.31)
and from left to right. You have also seen the primary symbols used
in automotive circuits in Unit 2 of this Module.
Refer to the manufacturer's service manual for specific details on how to read a
particular circuit diagram.
Trade of Motor Mechanic - Phase 2 Course Notes
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Volkswagen® Golf 1.4 petrol 1997-06 engine code AHW. Reproduced courtesy of Autodata®
Note: For training and testing purposes diagrams and information is available from automotive technical
manuals.
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Module 2 - Unit 6
Body Wiring, Lighting Circuits
Overview
A circuit diagram (also known as an electrical diagram or electronic
schematic) is a pictorial representation of an electrical circuit. It
shows the different components of the circuit and the power
and signal connections between the devices. Arrangement of the
components and interconnections on the diagram does not usually
correspond to their physical locations in the finished device.
Unlike a block diagram or layout diagram, a circuit diagram shows
the actual wire interconnects being used (although the picture does
not have to correspond to what the circuit actually looks like).
1.2 Component Identification ‘Group’
Codes
The individual components shown on schematic wiring diagrams
can be identified by a ‘Group’ code and also by a number. Then all
similar items are described by the same ‘Group’ letter, e.g. assemblies
i.e. Airbag, (driver) are identified by the letter ‘A’, switches ‘S’, all
fuses are identified by the letter ‘F’. The number or mathematical
figure after the letter will identify the circuit to which that fuse
belongs to. Light bulbs are given the letter ‘E’, motors ’M’ and all
relays ’K’, again, the number after the letter will identify the circuit
to which that component belongs to The full list of these is available
in the Technical support Information.
1.3 Connecting Wire Colour Code
The colours of the individual connecting wires can be identified by
letter code that may be an English or German language abbreviation
of the actual wire colour. The principal differences are;
White - ws (Weiss)
Black- sw (Swartz)
Red – rt (Rote)
Yellow – ge (Gelb)
The full list is available in the Technical support Information.
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Body Wiring, Lighting Circuits
1.4 Example Wiring Diagrams
The example wiring diagrams, beginning on page 19 are those of
a Volkswagen® Golf 1.4 petrol 1997-06 engine code AHW. This
first diagram is broadly representative of range of manufacturer’s
schematic diagrams. A special feature of this diagram is the terminal
identification code ‘X’. This terminal is the equivalent of terminal
No.75 (accessories) this means that it is live with the ignition on
but it is switched off during engine ‘cranking’. This is to retain
maximum battery voltage for engine cranking.
1.5 Symbols and Codes Used in the
Example Diagrams
Some of the symbols used in these diagrams are not strictly to
DIN standard, but instead they are a pictorial representation of the
individual components, e.g. the dim lamps are indicated differently
to the main beams. This is the system used by Autodata® and it
is designed help you to ‘read’ or interpret diagrams from all motor
manufacturers.
The following diagrams in this unit are an attempt to ‘lift’ or highlight
individual circuits from an overall diagram. You should study each
diagram carefully and then, when you feel confident, go further and
practice locating and tracing these circuits in other manufacturer’s
similar diagrams. Remember, the aim of this exercise is for you to
have the ability to develop and construct these circuits yourself.
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Body Wiring, Lighting Circuits
2.0 Primary Terminal Designation
Key Learning Points
•
Terminal designations: 30, 15, 31, 58, 56a, 56b, 49, 54, 61,
88a, 87, 86, 85 (58L, 58R)
The purpose of the terminal designation system for automotive
electrical systems is to enable correct and easy connections of the
conductors to the various devices especially in the event of repairs
and equipment replacement.
DIN* 72552 is a DIN standard for Automobile electric terminal
numbers, standardizing almost every terminal in an automobile with
a number code.
If the number of terminal designations is not sufficient (multiplecontact connections), the terminals are consecutively numbered
using numbers or letters whose representations of specific functions
are not standardized.
2.1 Electrical Connection (DIN)
Numbers
Terminal Designations: (Excerpts from DIN Standard 72 552),
these terminal designations do not identify the conductors, because
device with different terminal designations can be connected
at the two ends of each conductor. If the number of terminal
designations is not sufficient (multiple-contact connections), the
terminals are consecutively numbered using numbers or letters
whose representations of specific functions are not standardized.
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Body Wiring, Lighting Circuits
Terminal
Definition
15
Switched + downstream of battery (output of ignition/
driving switch)
Battery
30
Input from + battery terminal, direct
31
Return line to battery - battery terminal or ground,
direct
Turn Signal Flasher
49 and 49a, 49b All terminal no’s 49 have to with the turn signal
indicators
and 49c etc.
Starter
50
Starter control, ignition switch to the starter switch
54
Brake lamp
Lighting
55
Fog lamps
56(a, b)
Headlamp system
56a
High beam and Main beam indicator lamp
56b
Low beam
58
Side-marker lamps, tail lamps, license-plate lamps and
instrument-panel lamps
58L
Side-marker lamp, left
58R
Side-marker lamp, right
Alternators and voltage regulators
61
Alternator charge indicator light
Switching Relay
85
Output, actuator (end of winding to ground or
negative)
86
Start of winding
87
Output to the load from terminal 30
Normally closed contact
87a
*DIN “Deutsches Institut für Normung” is the German national
organization for standardization and is that country's ISO member
body.
Additional information is available from the automotive technical manuals.
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Body Wiring, Lighting Circuits
3.0 Electrical Connectors and
Their Function
Key Learning Points
•
Function and requirements of electrical connectors e.g. low
voltage loss, corrosion resistance, e.g. corrosion from use
of power/high pressure steam/chemical washer
3.1 Physical Requirements of Electrical
Connections
Electrical circuits require connections to assemble or join the power
supply to the desired load. Complex circuits will have switches, fuses,
possibly relays etc. and all the connectors and terminal connections
on the live and earth sides of these circuits. Circuits in the vehicle
are subjected to the stresses of vibration moisture and temperature
change also the possible corrosion by corrosive fluids and gases.
Vibration and movement due to thermal expansion also cause small
movement that result in friction between any connectors that are
simply clamped together.
3.2 Operational Requirements of
Electrical Connections
Therefore, electrical connectors must provide as easy a path as is
possible for the electrons to leave one side of the connection and
enter the adjoined connector. The connector must also provide
adequate electrical insulation for the current flowing through it and
it must prevent entry of moisture and dirt.
Connections must also be designed so that they can be readily
connected or disconnected and yet have a secure locking system.
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Body Wiring, Lighting Circuits
3.3 Service Requirements of Electrical
Connectors
Electrical connections should not be dismantled and reassembled
unless it is absolutely necessary, because each movement increases
the risk of the frictional resistance affecting the quality of the
surface to surface electrical contact.
It should not be possible to pair incorrect connectors/connections
together as the implications of this could be most serious, the
greatest dangers being short circuits and fire!
3.4 Consequences of Faulty Electrical
Connections
Modern vehicles use a number of electrical connectors to join
sections of the vehicle harness to vehicle system components.
Maintaining proper and safe function of these connectors is very
important as any corrosion that occurs in or on them can cause a
reduction in voltage and thus a system problem due to insufficient
voltage in a particular system. Poor connections are often the
cause of many automotive electrical system faults because a faulty
connection can increase current draw and have an adverse affect on
vehicle system operation.
They are generally water "resistant" but not "waterproof" and the
use of a pressure washer (particularly if solvents are used in the
washing process) directly on them should be avoided as this can
start the deterioration process.
3.5 Gold and Tin Coated Terminal Ends
Some connectors (terminal ends) are gold coated (plated) in order to
reduce potential oxidation corrosion and therefore provide a better
long term electrical connection between the items being connected
together. Do not mix gold coated and tin coated connections
together as the combination of the different metals will cause
electrolysis, which will then damage the electrical conductivity of
the connection.
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Body Wiring, Lighting Circuits
4.0 Electromagnetic Relays and a
Solenoids
Key Learning Points
•
Electromagnetic relay; small current controlling the flow
of a large current
•
Solenoid; mechanical movement from an electrical signal
4.1 Electromagnetic Relays
Relays are switches that are turned on and off by a small electrical
current. Inside a relay is an electromagnet. When a small current
energizes this electromagnet, it attracts an armature blade and
closes contact points. The large current that the relay is designed
to switch “on or off ” can then flow across these points. As long as
the small switching current flows through the relay coil the much
larger current will flow through its contact points.
The function of a relay in the lighting circuits is to reduce the
current demand on the control switch.
These contacts can be either normally-open, normally-closed, or
change-over contacts.
•
Normally-open contacts connect the circuit when the relay is
activated; the circuit is disconnected when the relay is inactive.
Normally-closed contacts disconnect the circuit when the
relay is activated; the circuit is connected when the relay is
inactive.
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Body Wiring, Lighting Circuits
•
Change-over contacts control two circuits: one normally-open
contact and one normally-closed contact.
Pin No. Designation
Description
85
Switching relay
Earth (end of winding to ground or
negative)
86
Switching relay
Positive (start of winding)
87
Switching relay
Output (to consumer e.g.: driving lamp)
87a
Switching relay
Alternative output (1st output, break
side)
30
Battery
Positive supply (Input from + battery
terminal, direct)
4.2Solenoids
Solenoid definition: linear movement from an electrical signal.
The modern starter motor is an example of where a solenoid switch,
works in a similar way to a relay. It is used as a switch where very
high amperage is required to start the vehicle.
When low-current power from the lead-acid battery is applied to the
solenoid usually through a key switch, its movement (caused by the
magnetic effect acting on its centre component) pulls out a small
pinion gear on the starter motor's shaft and meshes it with the ring
gear on the flywheel of the engine.
The solenoid also closes high-current contacts for the starter motor
and it starts to run.
If the engine starts the key switch is released, the solenoid is
de-energised and a spring returns in to the rest position thereby
disconnecting the supply from the starter motor and pulling the
small gear back off the starter gear.
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Body Wiring, Lighting Circuits
5.0 Relays in Lighting Circuits
Relay function; covered in 4.1
6.0 Terminal Designations of a
Trailer Wiring Socket/Plug
Key Learning Points
•
Relay and trailer wiring socket/plug terminal designations
•
Trailer lights; terminal identification e.g. 58, 54, 31 etc.,
correct termination/connection method.
6.1 Trailer Wiring Socket
The socket mentioned is the common 12N TYPE. This socket is
coloured black and houses 7 pins which are numbered 1 to 7 and
need to be connected using the correct wiring destinations as
follows.
Pin
Cable
Colour
1
Yellow
2
3
4
5
Front view of trailer socket
on vehicle.
6
7
Function
Left turn
signal
Blue
Fog lights
White Earth return
Right turn
Green
signal
Right hand
Grown
side light
Red
Brake lights
Left hand
Black
side light
Terminal
L
54G
31
R
58R
54
58L
Note: Refer to manufactures fitting instructions at all times. If fitting a trailer
socket on a vehicle that has a “can bus” system it is important to use the
manufactures trailer socket as this will comply with the necessary requirements
for that vehicle.
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Body Wiring, Lighting Circuits
7.0 The Basic Multiple Position
Switch Symbol
Key Learning Points
•
Switch symbols as per standard industry use, e.g. DIN
40900
Covered in next section.
8.0 Basic Dual/Triple Branch
Parallel Circuits
Key Learning Points
Practical Task
•
Source manufacturer’s wiring diagrams and from the overall
diagrams, identify and draw individual circuit layouts
•
Drawing of ignition/lighting etc., switch to automotive
manufacturer's example formats.
Please refer to your instructor for additional information, which is available from
the automotive technical manuals. Examples of in section 10.1
Component
Circuit Symbol
Function of Component
On-Off
Switch
(SPST)
SPST = Single Pole, Single
Throw. An on-off switch allows
current to flow only when it is in
the closed (on) position.
2-way
Switch
(SPDT)
SPDT = Single Pole, Double
Throw. A 2-way changeover
switch directs the flow of
current to one of two routes
according to its position.
Dual OnOff Switch
(DPST)
DPST = Double Pole, Single
Throw.
(DPDT)
DPDT = Double Pole, Double
Throw.
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Body Wiring, Lighting Circuits
9.0 Basic Schematic Wiring
Diagrams
Key Learning Points
•
Practical Task
Interpreting/drawing basic schematic lighting circuit
diagrams to identified manufacturer recommended format,
including relevant component symbols and terminal
identifiers
This is a practical task. Please refer to your instructor. Examples in section 10.1
9.1 Automotive Electrical Symbols
The following are some examples of the symbols used in circuit
diagrams. The actual layout of the components is usually quite
different from the circuit diagram.
Wires and Connections
Component Circuit Symbol
Wire
Wires
joined
In complex diagrams it is
often necessary to draw wires
crossing even though they
are not connected. I prefer
the 'hump' symbol shown on
the right because the simple
crossing on the left may be
misread as a join where you
have forgotten to add a 'blob'!
Wires not
joined
Trade of Motor Mechanic - Phase 2 Course Notes
Function of Component
To pass current very easily from
one part of a circuit to another.
A 'blob' should be drawn where
wires are connected (joined),
but it is sometimes omitted.
Wires connected at 'crossroads'
should be staggered slightly to
form two T-junctions, as shown
on the right.
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Body Wiring, Lighting Circuits
Power Supplies
Component Circuit Symbol
Function of Component
Supplies electrical energy.
The larger terminal (on the left) is
positive (+).
A single cell is often called a
battery, but strictly a battery is two
or more cells joined together.
Supplies electrical energy. A
battery is more than one cell.
The larger terminal (on the left) is
positive (+).
A safety device which will 'blow'
(melt) if the current flowing
through it exceeds a specified
value.
Cell
Battery
Fuse
Earth
(Ground)
A connection to earth. It is also
known as ground.
Output Devices: Lamps, Motor.
Component Circuit Symbol
Function of Component
Lamp
(indicator)
A transducer which converts
electrical energy to light. This
symbol is used for a lamp
providing illumination, for
example a car headlamp.
Motor
A transducer which converts
electrical energy to kinetic energy
(motion).
Switches
Component Circuit Symbol
Function of Component
On-Off
Switch
(SPST)
SPST = Single Pole, Single Throw.
An on-off switch allows current
to flow only when it is in the
closed (on) position.
SPDT = Single Pole, Double
Throw.
A 2-way changeover switch
directs the flow of current to one
of two routes according to its
position.
2-way
Switch
(SPDT)
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Body Wiring, Lighting Circuits
Component Circuit Symbol
Dual
On-Off
Switch
(DPST)
Reversing
Switch
(DPDT)
Function of Component
DPST = Double Pole, Single
Throw.
DPDT = Double Pole, Double
Throw.
Resistors
Component
Circuit Symbol
Resistor
Variable Resistor
(Rheostat)
Variable Resistor
(Potentiometer)
Function of Component
A resistor restricts the
flow of current.
This type of variable
resistor with 2 contacts
(a rheostat) is usually
used to control current.
Examples include:
adjusting dash panel
brightness.
This type of variable
resistor with 3 contacts
(a potentiometer) is
usually used to control
voltage e.g. fuel gauge.
Meters and Oscilloscope
Component
Circuit Symbol
Function of Component
Voltmeter
A voltmeter is used to
measure voltage.
Ammeter
An ammeter is used to
measure current.
Ohmmeter
An ohmmeter is used to
measure resistance.
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Body Wiring, Lighting Circuits
10.0Switch Controlled Fused
Lighting Circuits
Key Learning Points
•
Lighting circuits constructed to industry recommended
circuit diagram format only give example of diagram.
10.1 Sample Circuit Diagrams
Brake Lights
Stop or brake lights are red lights fitted to the rear of the vehicle.
According to the DIN 72552 they are number “54”. They are usually
incorporated in the taillight cluster although many vehicles have a
higher additional stop light mounted on top of the boot lid or on
the rear window called a high-level stop lamp (H 85 in diagram).
The stop lights are activated whenever the driver operates the foot
brake to slow or to stop the vehicle.
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Brake light bulbs.
This schematic diagram shows the brake light circuit. Switch S13 is the brake pedal switch and
the circuit is protected by fuse F13 which is 10 amps.
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Body Wiring, Lighting Circuits
Park & Tail Light Circuits
For motor vehicles and trailers, two red tail lamps operate when the
headlight switch is in the park position and the headlight position.
According to the DIN 72552 they are number “58”. The two lights
are located close to the widest points of the vehicle so that the vehicle
width can be seen by other road users. The bulbs are connected
in parallel to each other so that the failure of one filament will
not cause total circuit failure. A number plate illumination lamp is
usually connected in parallel to the tail lights and operates whenever
the tail lights are on.
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This schematic diagram shows a conventional parking/side light circuit . The circuit is protected
by fuses F4, F22, F23 and is switched through S3 (note the 58 on the switch contacts).
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Body Wiring, Lighting Circuits
Headlights
Modern headlights are electrically operated, positioned in pairs, one
or two on each side of the front of a moving vehicle. According
to the DIN 72552 they are number “56a and 56b” A headlamp
system is required to produce a low and a high beam, which may
be achieved either by an individual lamp for each function or by
a single multifunction lamp. High beams (called “main beams” or
“full beams” or “driving beams” in some countries) cast most of
their light straight ahead, maximizing seeing distance, but producing
too much glare for safe use when other vehicles are present on the
road.
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This schematic diagram shows a conventional headlamp circuit (Terminal 56a and 56b on light
switch) All bulbs are fused independently. Fuse numbers F18. F19, F20 and F21 are used.
You will notice that the dim circuit (T.56b) remain on with the headlights.
Components M35 and M36 are headlamp adjustment motors.
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Laws and Regulations
Headlights must be kept in proper alignment (aim) and condition according to
the NCT requirements for Headlamp Condition and Aim, Auxiliary Lamps
Condition and Aim
Fog Lights
Fog lights are used with other vehicle lighting in poor weather such
as thick fog, driving rain or blowing snow. Because fog is made up
of water droplets suspended in the air it can reflect headlights back
into your eyes at night. In such conditions, fog lights can help drivers
see further ahead and illuminate the road’s edges at reasonable
speeds and are used with “park” lights instead of headlights.
Fog lights will normally be wired with a relay. They may be wired
to work only with park lights and to turn off when headlights are
used.
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This schematic diagram shows a conventional fog light circuit. According to the DIN 72552 they
are number “55”. The front lamps (E14 and E15) are switched by relay (K2). The earth for this
relay is through the headlight filament which means that the fog lamps will only operate when
the headlights are off. Fuse (F3) protects the relay and fuse (F36) protects the lighting circuit.
25
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Body Wiring, Lighting Circuits
Reverse Lights
The reversing lights are white lights fitted to the rear of a vehicle.
They provide the driver with vision behind the vehicle at night
and also alert other drivers to the fact that the vehicle is to be
reversed.
When the ignition switch is on and the vehicle is placed in reverse
gear current flows from the battery, through the ignition switch, to
the closed reversing light switch on the transmission.
Electrical current flows across the closed switch to the reversing
lights and then returns to the battery by the earth return system.
Driving Lights
Driving lights are used to supplement vehicle headlight systems.
The driving lights are fitted to the front of the vehicle and provide
higher intensity illumination over longer distances than standard
headlight systems. NCT regulations specify the limitations in relation
to the positioning of driving lights.
There are many types of driving lights available. They come in
different sizes, shapes and varying bulb wattage.
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Indicators
The turn signal indicators are visual signalling devices to indicate
the intention to turn. Once they are activated, they continue until
the switch is cancelled either by the operator or by a cancelling
mechanism in the switch. The cancelling mechanism operates after
a turn has been completed and the steering wheel is returned to the
straight ahead position.
The circuit consists of:
•
battery
•
fusible links and fuses
•
ignition switch
•
flasher unit
•
a three position switch used as the direction indicator switch
•
lights at the front and rear of the vehicle
•
pilot lights mounted in the instrument cluster to indicate to
the driver which way the switch has been operated
•
wiring to connect all of the components
•
the ground circuit to return the electrical current to the
battery
If the indicator switch is turned to indicate a right-hand turn, current
from the battery flows through the fusible link to the ignition switch,
where it is directed through a fuse to the flasher unit.
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11.0 Relay Controlled Auxiliary
Lighting Circuits
Key Learning Points
•
Practical Task
Lighting circuits constructed to industry recommended
circuit diagram format only
This is a practical task. Please refer to your instructor for additional information,
which is available from the automotive technical manuals.
12.0To Connect a Trailer Light
Assembly
Practical Task
This is a practical task. Please refer to your instructor.
13.0Diagram of Basic Standard
Circuits
Key Learning Points
•
Practical Task
Source manufacturer’s wiring diagrams and from the overall
diagrams identify and draw individual circuit layouts.
This is a practical task. Please refer to your instructor for additional information,
which is available from the automotive technical manuals. Examples of in
section 10.1.
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14.0The Term 'BUS' as Used in
Automotive Electrical Systems
Key learning Points
•
Bus, a network of computers linked together to communicate
electrically, (in-vehicle network) called a communication bus
or more often called the 'BUS'
14.1’BUS’ Explained
In automotive systems the term “bus” can connect several control
units or devices together over the same set of wires. A comparison
can be made to a highway with two-way traffic and traffic emerging
onto the highway from different locations. Access to the highway
is controlled by traffic lights (can-bus).
This system is referred to as a Controlled Area Network BUS or
CAN BUS. “CAN” stands for Controller Area Network meaning that
control units are networked and they interchange data. It uses two
thin wires to connect, or multiplex, all the control units and their
sensors to each other. The advantage of a multiplex network is
that it enables a decreased number of dedicated wires for each
function and therefore a reduction in the number of wires in the
wiring harness, reduced system cost and weight, improved reliability,
serviceability and installation. In addition, common sensor data,
such as vehicle speed, engine temperature, etc. are available on the
network, so data can be shared, thus reducing the number of sensors.
Also, networking allows greater vehicle content flexibility because
functions can be added or modified through software changes.
A diagnostic tool can be connected to the CANBUS to extract
operational information to assist in diagnosis and fault finding.
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15.0 In-Vehicle Network
Developments
Key Learning Points
•
Integrated control units, more sophisticated vehicle control,
e.g. engine ECU to ABS - ATC (engine power management),
allows different systems to share sensors, saves weight and
reduces complexity of stand alone systems
15.1 Networking & Multiplexing
Even the most basic vehicles include many electronically controlled
systems. If each electronic system had its own ECU, harness and
sensors, the weight of the added components would negate any
efficiency it provided. A vehicle’ multiple electronic systems could
require over 1.6 Kilometres of insulated wiring, consisting of around
1000 individual wires and many terminals.
One solution to the problem is the use of a system that integrates
sensors into a common wiring harness by combining all the individual
systems, where possible, into a multiplexed serial communications
network, so they can share the information. An added advantage is
that it saves weight as it allows different systems to share sensors
and reduces complexity of stand-alone systems.
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16.0Location and Voltage Drops
on the Earth Connections
Key Learning Points
•
Practical Task
The earth point connections of primary/principal electrical
circuits on training vehicles/units, e.g. lighting, fuel pump
etc., examined for location, connection method and voltage
drop.
This is a practical task. Please refer to your instructor for additional information,
which is available from the automotive technical manuals.
17.0Tungsten, Halogen and Xenon
Bulbs
Key Learning Points
•
Bulbs, connectors, moisture seals handled and refitted
correctly, special coated bulb use (prevent yellowing of
plastic lens).
17.1 Light Bulbs
A lamp bulb consists of a fine coil of tungsten wire, called a filament,
enclosed in a clear glass envelope from which all air has been
removed. Passing a current through the filament raises its temperature
to a white heat and causes it to give off an incandescent light.
Removing air from the glass envelope prevents oxidation of the
filament when it is in operation and increases the filament life.
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In high wattage bulbs, particles of tungsten can boil off the filament,
even though the air is removed and eventually cause filament failure.
To prevent this, the glass envelope is filled with an inert gas - such
as argon - which does not react with the tungsten and this slows
the boiling off of the filament. In some applications special coated
bulbs are fitted, this helps prevent “yellowing” of plastic lenses.
All manufactures have procedures for removing and fitting bulbs
these should be followed at all times. When fitting a halogen bulb
is important not to contaminate the surface of the bulb with your
hand as this will result in premature failure of the bulb. The focusing
of the headlights is also advisable after fitting new headlight bulbs
to ensure they are properly aligned to current NCT regulations.
Bulb Information
All bulbs have letters and numbers stamped on the bulb which
indicate the power consumed by bulb operation at the nominal
operating voltage.
For instance, in a 12V/21W bulb the filament will consume 21 watts
of power when 12 volts is applied across the filament.
While the wattage is not necessarily an indication of light output,
it can be generally assumed that the higher the wattage, the greater
the light output will be. If a higher wattage bulb is inserted than
what is recommended this could lead to more heat been generated
and the possibility of a fire starting.
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The common bulbs used in automobiles are:
•
Festoon bulbs used in many interior lights.
•
Bayonet connectors used in circuits lighting for park lamps;
stop lamps; tail lamps; number plate lamps; some early
headlamps.
•
Wedge bulb use in many dash clusters.
17.2 Xenon HID Headlights
High Intensity Discharge or HID lights can be recognized by their
extremely bright white or bluish light. They provide the motorist
with better illumination than other types of lights. HID lights
improve visibility. Drivers using HID lights are able to see the road
ahead for approximately 100 meters, compared to about 60 meters
for a halogen system.
In comparison with halogen lights, HID headlights can be up to 3
times brighter, are more efficient in converting electrical energy into
light energy, have a longer service life and the light colour is whiter
or closer to daylight.
They operate on a gas discharge bulb system and consist of a light,
bulb, ballast and special high voltage circuitry. HID headlights
systems do not use a filament in the bulb. They have the inert gas
Xenon inside the bulb, with two electrodes that have an air gap
between them in a glass tube. A high voltage is applied between the
electrodes. This causes an arc to form, which vaporizes the gases
and solids so they emit a bright light. The voltage required to strike
and maintain the arc is very high - typically up to 20, 000 volts.
Therefore when workings on these systems refer to manufactures
procedures at all times.
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18.0Servicing Lamps
Practical Task
This is a practical task. Please refer to your instructor.
19.0NCT/DoT VTM Regulations
for Condition of Lamps
Key Learning Points
•
NCT/DoT VTM regulations for Stop Lamps, Rear Lamps
and Registration Plate Lamps, Indicators/Tell Tales, Side
Lamps (Front Position Lamps), Headlamp Condition,
headlamp Aim, Auxiliary lamp Condition, Auxiliary Lamp
Aim and Reflectors
19.1 NCT Body Wiring and Lighting
Circuit Requirements
Please refer to the current NCT reference manual, item No’s 26 to
34 inclusive for NCT requirements for Passenger Vehicle lighting
systems.
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20.0Focusing Headlights
Key Learning Points
Practical Task
•
Lights focused to NCT/DoT VTM standards.
•
Beam setting machine and vehicle correctly prepared and
set up, e.g. light lens clean, vehicle level etc., machine in
longitudinal and latitudinal parallel with vehicle etc..
This is a practical task. Please refer to your instructor.
21.0Diagnosing Electrical Circuits
Key Learning Points
•
Measurement and diagnosis of electrical circuit faults on
the electrical circuits of an operational vehicle/training
unit using a multimeter, current carrying capability of;
conductors, switch contacts and connections.
•
Incorrect use of the ammeter resulting in short circuits.
•
Correct use of the standard and inductive multimeter.
The use of a multimeter is covered in module 2 unit 2.
Practical Task
This is a practical task. Please refer to your instructor.
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22.0The Effect of Wrong Fuse or
Bulb
Key Learning Points
•
Incorrect fuse; inability to carry circuit maximum load, or
circuit not protected adequately
22.1Fuses
Fuses and circuit breakers are designed to break the circuit if current
flow is excessive. The most common kinds are fuses, fusible links
and circuit breakers. They are all rated in amperes. Their ratings are
usually marked on them. It is important to fit the correct size of
fuse. To small a rating will not allow enough current to flow in the
circuit and too large a rating may not protect the circuit properly.
Fuses are typically used in lighting and accessory circuits where
current flow is usually moderate. Changing the wattage of the bulb
i.e. (incorrect bulb type) will alter the current required. If a higher
wattage bulb is inserted this could lead to over loading of the
electrical system and the possibility of a fire starting.
A fusible link is typically placed near the battery and, except for the
starter motor; it carries the current needed to power an individual
circuit, or a range of circuits.
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23.0Crimped Joints on Light
Cables
Key Learning Points
•
Crimp cable joints made correctly, minimum insulation
removed, conductor material not damaged/cut etc..
23.1 Stripping Wire Insulation
Preparation and Safety
Objective
Correctly strip an electrical wire and connect a solderless connector.
Personal Safety Whenever you perform a task in the workshop you must use personal
protective clothing and equipment that is appropriate for the task
and which conforms to your local safety regulations and policies.
Among other items, this may include:
•
Work clothing - such as coveralls and steel-capped footwear
•
Eye protection - such as safety glasses and face masks
•
Ear protection - such as earmuffs and earplugs
•
Hand protection – such as rubber gloves and barrier cream
If you are not certain what is appropriate or required, ask your
instructor.
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Safety Check
Points to Note
Body Wiring, Lighting Circuits
•
Never use a sharp blade or knife to remove insulation. You
can cut yourself seriously if the blade slips.
•
Wire stripping pliers have sharp edges and require a tight grip.
Do not trap your skin between the jaws; otherwise you risk a
severe cut.
•
When removing the insulation from wire, push away from you
rather than towards you.
•
Make sure that you understand and observe all legislative
and personal safety procedures when carrying out the
following tasks. If you are unsure of what these are, ask your
instructor.
•
An insulating layer of plastic covers electrical wire used in
automotive wiring harnesses.
•
When electrical wire is joined to other wires or connected to
a terminal, the insulation needs to be removed.
•
Wire stripping tools come in various configurations. They all
perform the same task. The type of tool you use or purchase
will depend on the amount of electrical wire repairs you
perform.
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Step-by-Step Instruction
1.
Choose the correct stripping tool: The purpose of a wire stripping
tool is to allow you to remove the insulation from around
the copper core of a cable without damaging the cable or
yourself. Never use a knife or other type of sharp instrument
to cut away insulation from a cable, as it is very easy for these
to slip and you can injure yourself. Using side cutters or pliers
can also be dangerous; and these are also less effective as
they often cut away some of the strands of wire as well. This
is known as ringing the wire, which effectively reduces the
current carrying capacity of the wire.
2.
Select the correct gauge hole: Using the correct tool is much safer
and more effective. Wire strippers can remove the insulation
from different gauges of cable, so select the hole in the stripper
that is closest to the diameter of the core in the cable to be
stripped.
3.
Cut the insulation: Place the cable in the hole and close the jaws
firmly around it to cut the insulation. If you have selected the
right gauge, then this will cut through the insulation but not
through the copper core. Only remove as much insulation
as is necessary to do the job. Too little bare wire may not
achieve a good connection and too much may expose the wire
to a potential short circuit with other circuits or to ground.
Removing more than 1.2 centimetres of insulation at a time
can also stretch and damage the core.
4.
Remove the insulation: Some strippers automatically cut and
remove the insulation. Others just make the cut and hold
the cable tightly and you need to pull firmly on the wire to
remove the insulation and strip out the copper core. To keep
the strands together, give them a light twist.
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Self Assessment
Q1: ‘Work’ is achieved when the energy is:
(Tick one box only)
 1. Released



1. Stored
3. Captured
4. Harnessed
Q2: How is the stop lamp switch connected in relation to
the stop lamp circuit? (Tick one box only)
 1. Series



2. Parallel
3. Series-parallel
4. None of these
Q3: How is the stop lamp bulbs connected in relation to
each other? (Tick one box only)
 1. Series



2. Parallel
3. Series-parallel
4. None of these
Q4: 1) What is bulb power measured in and 2) What does
this indicate? (Tick one box only)
 1. 1) Volts, 2) EMF



2. 1) Volts, 2) current flow
3. 1) Watts, 2) brightness
4. 1) Watts, 2) power consumption
Q5: A 24V 21W bulb consumes more power than a 12 V 21W
bulb. (Tick one box only)
 1. True

2. False
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Q6: What is the purpose of fuses and circuit breakers?
(Tick one box only)
 1. To protect the circuit and components from excessive
current flows

2. To protect the circuit and components from excessive
resistance that is over the safe operating limits as specified
by their manufacturer

4. Mechanical energy into electrical energy
Q7: Why are vehicles fitted with individually different types
of lighting system? (Tick one box only)
 1. It is simpler to construct in the first place

2. Because if one system fails the others can still work
independently of the failed system

3. One system operates off of the other and it is easier to
trace faults when a lamp fails

4. Because one fuse can be used for all systems
Q8: Wiring diagrams give information about:
(Tick one box only)
 1. Voltage applied to a circuit



2. Current flow to components
3. Circuit connections and colour codes
4. Circuit resistance
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Suggested Exercises
1.
Use an electronic data facility to procure manufacturer’s
appropriate data for use with practical exercises.
2.
From a selection of manufacturers' electrical circuit diagrams,
identify and draw lighting circuit diagrams.
3.
On lighting circuit training units/systems, construct standard
parking, brake and dual filament lighting circuit.
4.
Construct a relay controlled auxiliary lighting circuit.
5.
Focus training vehicle headlights to NCT/DoT VTM
standards.
6.
Use a multimeter to locate/rectify circuit faults.
Training Resources
•
Technical information in book/electronic form on schematic
wiring circuit diagram representation
•
Purpose designed, basic schematic lighting circuit diagrams
that progressively lead to manufacturer standards, lighting
circuit diagrams
•
Automobile lighting circuit training units/systems complete
with power supply
•
Selection of automobile head light bulbs and light units (bench
units)
•
Training vehicles with headlight units suitable for beamsetting
•
Multimeters, copy of NCT/DoT VTM manuals
•
Beamsetter on suitable workshop floor area
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Task Sheets
Aiming Headlights
Preparation and Safety
Objective
Use a headlamp adjuster unit to aim headlights.
Personal Safety
Whenever you perform a task in the workshop you must use personal
protective clothing and equipment that is appropriate for the task
and which conforms to your local safety regulations and policies.
Among other items, this may include:
•
Work clothing - such as coveralls and steel-capped footwear
•
Eye protection - such as safety glasses and face masks
•
Ear protection - such as earmuffs and earplugs
•
Hand protection – such as rubber gloves and barrier cream
•
Respiratory equipment – such as face masks etc.
Safety Check
Make sure that you understand and observe all legislative and
personal safety procedures when carrying out the following tasks.
If you are unsure of what these are, ask your instructor.
Points to Note
•
Check manufactures settings and current NCT settings. If you
are unsure of what these are, ask your instructor.
•
Refer to the manufacturer's manual for specific information
regarding headlight aiming. They may also suggest that a load
be placed in the vehicle.
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Step-by-Step Instruction
1.
Check tire pressures: Make sure the car is on an even and level
surface and that the tires are inflated properly. Over loading
the rear of the vehicle can alter the alignment, so make sure
the check is done according to the manufacturers loading
recommendations.
2.
Position vehicle: Move the vehicle into the correct position in
relation to the headlamp aligner unit following the equipment
manufacturer instructions.
3.
Check low beam settings: Turn the headlights on to a low beam
setting. Check readings against manufactures settings.
4.
Check high beam settings: The high beam should be cantered,
falling on the intersections of the horizontal and vertical
marks.
5.
Adjust headlight alignment: If necessary, locate the adjustment
screws on the headlight and turn them so the lights point to
the correct places.
Checking & Changing a Headlight Bulb
Preparation and Safety
Objective
Check and change a headlight bulb.
Personal Safety Whenever you perform a task in the workshop you must use personal
protective clothing and equipment that is appropriate for the task
and which conforms to your local safety regulations and policies.
Among other items, this may include:
Safety Check
•
Work clothing - such as coveralls and steel-capped footwear
•
Eye protection - such as safety glasses and face masks
•
Ear protection - such as earmuffs and earplugs
•
Hand protection – such as rubber gloves and barrier cream
•
Respiratory equipment – such as face masks etc.
Make sure that you understand and observe all legislative and
personal safety procedures when carrying out the following tasks.
If you are unsure of what these are, ask your instructor.
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Points to Note
Body Wiring, Lighting Circuits
•
There are many types of headlight bulbs available. Always
make sure that you replace a bulb with one of exactly the same
type. Otherwise, change both lights at once, so they always
show the same intensity in lumens.
•
Sealed beam units require that the whole unit be replaced
when one filament has failed. If the reflector in the lamp unit
shows signs of internal blistering, that also indicates that you
must change the unit.
•
If both lights operate but are not bright when switched on,
start the engine to see if this solves the problem. The battery
may be in a poor state of charge. Another explanation is that
the system may have a bad ground connection. This would
have to be checked with a DVOM.
•
Touching a new halogen bulb with your fingers can leave some
greasy residue from your fingers on the outer surface. This
can cause the bulb to burn out very quickly. If you inadvertently
touch the bulb, clean it with an alcohol-based substance.
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Step-by-Step Instruction
1.
Check headlight operation: Assessing headlight operation is always
best carried out in a low light environment. Switch the vehicle
headlights on to low beam and then switch to high beam.
Check that the main beam indicator on the instrument panel
is operating. Note the change in the intensity of the lights.
If one of the lights does not operate that headlight will need
replacement.
2.
Identify headlight type: Determine the type of lamp fitted to
the vehicle and obtain a replacement. Many vehicles today
are equipped with halogen type headlights. These are twice
as powerful as older sealed-beam units and need to be
handled carefully. Always follow the manufacturer’s handling
instructions.
3.
Access the lamp socket: Unplug the electrical connector at the
back of the lamp unit. On most vehicles it is not necessary
to remove the lamp unit from the vehicle. Unscrew the bulbretaining ring.
4.
Remove and replace the old bulb: Remove the old bulb and replace
it with the new one. Handle the new bulb only by its base or,
if supplied, by the card cover. It is very important that you
never touch the surface of the bulb with your fingers, as this
will cause it to burn out very quickly.
5.
Replace the headlight unit and test: Replace the unit and the retaining
ring or bulb assembly and then re-plug the connector. Switch
on the lights again to confirm that they are both operating
correctly.
Checking & Changing an Exterior Light
Bulb
Preparation and Safety
Objective
Check and change an exterior light bulb.
Personal Safety Whenever you perform a task in the workshop you must use personal
protective clothing and equipment that is appropriate for the task
and which conforms to your local safety regulations and policies.
Among other items, this may include:
•
Work clothing - such as coveralls and steel-capped footwear
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•
Eye protection - such as safety glasses and face masks
•
Ear protection - such as earmuffs and earplugs
•
Hand protection – such as rubber gloves and barrier cream
•
Respiratory equipment – such as face masks etc.
Safety Check
Make sure that you understand and observe all legislative and
personal safety procedures when carrying out the following tasks.
If you are unsure of what these are, ask your instructor.
Points to Note
•
Make sure that the fuses are in good condition before
attempting to change a bulb in a circuit that has more than
one bulb, such as the turn signal circuit. If none of the bulbs
are working, there may be a bigger problem to resolve.
•
Many light bulbs have more than one filament inside them.
These bulbs normally have offset pins to ensure proper
locking in the socket. Be sure to look carefully at the bulb
you are replacing to make sure you do not try to force the
bulb in the wrong way.
•
Some bulbs have a coloured glass envelope that enables them
to be used with a clear lens. If you replace a bulb of this type,
make sure that you replace it with one of the same colour.
Step-by-Step Instruction
1.
Access the bulb: Determine the method used to secure the lamp
unit or lens cover and remove the cover to expose the bulb.
If no screws are found on the lens cover, it may be necessary
to remove the entire assembly to access the bulb.
2.
Remove the bulb: If the bulb is pin-mounted, gently grip the
bulb and push it inwards. Turn the bulb in a counter-clockwise
direction and remove it from the bulb holder.
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3.
Check bulb holder for corrosion: Inspect the bulb holder to make
sure there is no corrosion. If there is, clean it with abrasive
tape.
4.
Insert the new bulb: Insert the new bulb into the bulb holder,
depress it fully, turn it clockwise and release it. Make sure the
bulb is secure and test its operation by switching it on and
off.
5.
Replace cover and test: Replace the cover and test it again.
Checking Lighting & Peripheral Systems
Preparation and Safety
Objective
Check peripheral lighting systems.
Personal Safety Whenever you perform a task in the workshop you must use personal
protective clothing and equipment that is appropriate for the task
and which conforms to your local safety regulations and policies.
Among other items, this may include:
•
Work clothing - such as coveralls and steel-capped footwear
•
Eye protection - such as safety glasses and face masks
•
Ear protection - such as earmuffs and earplugs
•
Hand protection – such as rubber gloves and barrier cream
•
Respiratory equipment – such as face masks etc.
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Safety Check
Make sure that you understand and observe all legislative and
personal safety procedures when carrying out the following tasks.
If you are unsure of what these are, ask your instructor.
Points to Note
•
Be sure to work in a systematic manner or you could miss a
faulty bulb or another component.
•
A vehicle may have warning lights that will activate only if
that circuit is in use. You may need to turn that circuit on to
see the warning light. If you are unsure of where these are,
ask your instructor.
Step-by-Step Instruction
1.
Check instrumentation: In a darkened area, turn on the ignition.
The dash warning lights should be displayed. Start the engine.
If any warning light stays on when the engine is started, it could
indicate a problem in one of the car’s safety or mechanical
systems. If you are unsure about what any of the warning
lights mean, consult the manufacturer’s manual.
2.
Check the car horn: Make sure the car horn is working. If the
horn is not working, locate it under the hood with the help
of the manufacturer’s manual. Check the wiring to make sure
there is a good contact. If necessary, use a DVOM to isolate
the fault.
3.
Check rear lights: Have someone stand behind the vehicle to
report any problems and then turn the ignition on. Switch on
the park lights and tail lights. Do the same for left and right
turn indicator lights. Depress the brake pedal to make sure
the brake lights work.
4.
Check front lights: With somebody in front of the vehicle, make
sure the high and low headlight beams, the park lights and the
turn indicators are all working properly.
5.
Check interior lights: With the interior light switch in the correct
position, open the driver’s side door to make sure the interior
lights work. If any of these lights do not operate, you may
need to replace a bulb, or a fuse. Check the fuse first, using a
DVOM to check continuity. If the fuse is at fault you should
report this to your instructor, as there could be a more serious
fault in the vehicle’s wiring system.
Trade of Motor Mechanic - Phase 2 Course Notes
49
Revision 3.0 November 2013
Module 2 - Unit 6
Body Wiring, Lighting Circuits
Suggested Further Reading
•
Advanced Automotive Diagnosis. Tom Denton. ISBN
0340741236
•
Automobile Electrical and Electronic Systems (3rd Edition).
Tom Denton. ISBN 0750662190
•
Automotive Mechanics (10th Edition). William H. Crouse and
Donald L. Anglin. ISBN 0028009436
•
Bosch Automotive Electrics Automotive Electronics: Systems and
Components (4th Edition). Robert Bosch. ISBN 0837610508
•
Bosch Automotive Handbook (6th Edition). Robert Bosch.
ISBN 1860584748
•
Bosch Automotive Technology Technical Instruction booklet
series (numerous titles)
•
Hillier’s Fundamentals of Motor Vehicle Technology: Book
One (5th Edition). V.A.W. Hillier and Peter Coombes. ISBN
0748780823
•
Hillier’s Fundamentals of Motor Vehicle Technology: Book
Two (5th Edition). V.A.W. Hillier and Peter Coombes. ISBN
0748780998
•
Modern Automotive Technology. James E. Duffy. ISBN
1566376106
•
Motor Vehicle Craft Studies - Principles. F.K. Sully. ISBN
040800133X
•
National Car Test (NCT) Manual (Department of Transport,
Vehicle Testers Manual - DoT VTM). Department of
Transport
•
Transmission, Chassis and Related Systems (Vehicle Maintenance
and Repair Series: Level 3) (3rd Edition) John Whipp and Roy
Brooks. ISBN 186152806X
•
Vehicle and Engine Technology (2nd Edition). Heinz Heisler.
ISBN 0340691867
•
http://www.cdxglobal.com/
•
http://auto.howstuffworks.com/
•
http://www.autoshop101.com/
•
http://www.cdxetextbook.com/
•
Automotive Encyclopedia and Text Book Resource (CD version
of e-textbook), Available from your instructor.
Trade of Motor Mechanic - Phase 2 Course Notes
50
Revision 3.0 November 2013
Notes
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